The Hydraulic flow dividers and integrators operate on the principle of throttling regulation. Liquid flows are compared by permanent or changeable measuring throttles, while regulation is performed by the regulating slide valves being displaced under the influence of differantial pressures, forming accessory throttles, thus ensuring the desired ratio of division i.e. integration independent of the hydraulic load.
With hydraulic gear drives synchronization independent of the load on the wheels of a vehicle used to be realized by the aid of the traditional regulating slide valves having double control-edges, by connecting three current dividers or by installing the regulating slide valves and measuring throttles in a common housing.
FIG. 1 shows this known solution, where three flow dividers having double-control edges are interconnected. With this solution it seems to be disadvantageous in that the minimal diffential pressure needed for regulation appears twice on the measuring throttles, furtheron, the liquid flow passing through the first regulating slide valve is larger than those passing through the second and third regulating slide valve and accordingly, these have expediently different geometrical dimensions.
A further disadvantageous feature lies in that the number of the measuring throttles is just the double of the number of the regulating slide valves, and the cross-section of the measuring throttles is also different, even at an equal ratio of division.
From technical literature a solution is known, with which regulation of the liquid flow is realized by means of regulating slide valves having a single control edge. FIG. 2 shows the simplified theoretical schematic of the known solution. From the figure it becomes obvious that the minimal differential pressure needed for the regulation of the liquid flow appears only once on the measuring throttles and as a consequence, energy loss will be less, and assuming an equal ratio of division, identical liquid flows will flow through the regulating slide valves, so that their geometrical dimensions are expediently identical, enabling a simpler production technology and resulting in smaller dimensions and reduced mass. The number of the measuring throttles equals the number of regulating slide valves, which equals the number of loads and in addition, the measuring throttles have equal cross-sections enabling cheaper production and structural design. Beside the advantages enumerated, this solution has several disadvantages in view of the objective: since recoupling between the regulating slide valves is formed by a liquid, expediently oil streaming in a closed space with maintenance of a constant volume, so that dimensioning of the volume in itself represents an extremely complicated task; any change in the number of the regulating slide valves required by the increase or decrease of the number of hydraulic loads becomes possible only by the complete reconstruction of the flow divider and integrator.
A further drawback of this solution is that in contrast to the solution with the double control-edge, the regulating differential pressure always puts two regulating slide valves into motion and as a consequence, effects of frictional force will be always larger and regulation will be more inaccurate, while, at the same time, regulating slide valves could not be completely eliminated in the course of regulation.